True, but a spare wheel would be sprung weight.
Unsprung weight is bad news. That's why race cars, and some road cars (E-type for example) had inboard brakes, to reduce unsprung mass.
Run-flats have a higher rotational inertia as well, adversely affecting braking and acceleration.
Can you tell i really don't like them? lol
Bought a Michalin twin foot pump a few years back, I hate those petrol Garage ones. Got my RF 195/55/R16 87H set to 2.2 Bar or 32 Psi as the sticker in the door suggests.
Mini as it was. As it is. As it always will be. Everyone is entitled to their opinion, it's up to you to decide if it counts!
Went into 3 different Tyre places today (long story short two of them would not do a puncture repair on a run flat) Anyway I asked them what they suggested I should run the tryes at pressure wise.
They gave me a print out and according to their computers, the 205/45/17 runflats (one, cooper and S) should be 36psi (front and back), and 39psi loaded. The JCW Cooper S can't remember the tyre is 39psi and 41 loaded. This is all very strange.
I should have said the figures I quoted were for the R50/53 The R56 must be different
"I have not failed. I've just found 10,000 ways that won't work." - Thomas Edison
Mutley - May 2003 Chili Red 'One'